1. Field of the Invention
The present invention relates to an agitator, and more particularly, to an agitator capable of improving durability of an agitating hook for agitating a high viscosity material with rotor blades, and an agitating hook provided therein.
2. Discussion of Related Art
In general, polymerization refers to a reaction in which small molecules are repeatedly added to form a single long continuous chain. Here, a small unit molecule is referred to as a unit body. An agitator is needed in a polymerization reactor, which performs polymerization, to agitate a high viscosity fluid or gel-type material having a viscosity higher than a predetermined level.
FIG. 1 is a perspective view showing a configuration of a conventional agitator, and FIG. 2 is an enlarged perspective view of a portion of the agitator shown in FIG. 1.
As shown in the drawings, the agitator has a substantially cylindrical shape, in which an agitation member is installed. The agitator shown in FIG. 1 may be installed in plural in the cylinder to perform agitation. A rotary shaft 3 is rotatably installed at a center in an inner space defined by an inner wall 1 of the agitator. The rotary shaft 3 receives power from a power source such as a motor to be rotated.
A plurality of rotor blades 5 are installed at an outer circumference of the rotary shaft 3. The plurality of rotor blades 5 may be installed at the outer circumference of the rotary shaft 3 at a predetermined interval. The rotary blades 5 may be rotated together with the rotary shaft 3 to substantially agitate a high viscosity material. The rotary blade 5 has a substantially fan-shape.
In addition, agitating ribs 7 are formed at ends of the rotary blades 5, respectively. The agitating ribs 7 perpendicularly project from the ends of the rotor blades 5. Referring to FIG. 3, the agitating rib 7 perpendicularly extends from the end of the rotor blade 5 in both directions. Meanwhile, the agitating rib 7 passes through a rib passing part 13, which will be described.
An agitating hook 10 is installed at the inner wall 1 to agitate and crush a high viscosity material. The agitating hook 10 may be provided around the inner wall 1 in plural. As shown in FIG. 2, the agitating hook 10 is formed of a pair of symmetrical members spaced apart a predetermined distance from each other. In addition, the rotor blade 5 and the agitating rib 7 pass through the agitating hook 10 to agitate and crush the high viscosity material.
Referring to FIG. 2, the agitating hook 10 includes support parts 12 projecting from the inner wall 1 of the reactor and spaced apart a predetermined gap from each other, connecting parts 14 extending from tips of the support parts 12 in facing directions, and parallel parts 16 parallelly extending from tips of the connection parts 14.
In addition, the rib passing part 13 through which the agitating rib 7 passes is formed between the support parts 12, and a blade passing part 17 through which the rotor blade 5 passes is formed between the parallel parts 16. The rib passing part 13 has a relatively larger width than that of the blade passing part 17, because a width of the agitating rib 7 is larger than that of the rotor blade 5.
In order to prevent interference between the agitating hook 10 and the rotor blade 5 during rotation, a predetermined gap must be formed therebetween. This is also similar to the agitating rib 7. This is shown in FIG. 3 well. That is, the high viscosity material passes through the gap formed between the agitating hook 10 and the rotary blade 5 to be crushed.
Specifically describing the agitation and crush operation of the agitating hook 10, first, a high viscosity fluid or gel-type material is inserted into the agitator. In general, a high viscosity material agitated in the agitator has a viscosity of 10,000 cp or more. Such a material is likely to be changed from a liquid phase into a solid phase so that the volume thereof is abruptly expanded.
When the high viscosity material is input, the material is conveyed from an inlet port to an outlet port and sequentially converted from the liquid phase into a gel type and from the gel type into a solid phase. In particular, as described above, the volume is abruptly expanded while the gel-type is converted into the solid phase. The solid lumps pass through the agitating hooks 10 to be agitated and crushed by rotation of the rotor blades 5.
However, the conventional art as described above has the following problems.
As shown in FIGS. 3 and 4, the agitating hook 10 through which the rotor blade 5 passes has a constant gap from an inlet port through which the rotor blade 5 enters and an outlet port through which the rotor blade 5 leaves. Since the gap between the rotor blade 5 and the agitating hook 10 is constant, a pressure applied to the agitating hook 10 is increased from the inlet port to the outlet port as shown in FIG. 4.
When the pressure applied to the agitating hook 10 is not constant and increased as it goes toward the outlet port, a torsional moment is applied to the agitating hook 10 due to a difference in pressure. That is, the agitating hook 10 receives a force to be rotated in an arrow direction shown in FIG. 5.
Since such a moment is repeatedly applied to the agitating hook 10 whenever the rotor blades 5 continuously pass through the agitating hook 10, the agitating hook 10 may be failed due to fatigue. In particular, when the moment is continuously applied to the support parts 12 of the agitating hook 10, the agitating hook 10 may be broken to be separated from the inner wall 1.
Eventually, when the agitating hook 10 is broken, since the agitator cannot be normally operated, agitation efficiency is decreased and repair cost is increased.